A conventional elevator includes a car frame supported by a hoisting machine rope, and the car frame is constituted by a lower frame, upright columns, and an upper frame. A cab that passengers enter and leave is supported in the interior of the car frame. The car frame and the cab are separate structures, and therefore sufficient strength must be secured in each. For example, the upper frame of the car frame must be strong enough to be able to withstand an offset load acting on a floor plate of the cab, while a ceiling plate of the cab must be strong enough to be able to withstand the weight of a maintenance worker or a heavy component placed thereon during installation or maintenance. In a conventional elevator, strength must be secured in both the upper frame and the ceiling plate, leading to overall increases in the number of components and the mass of the elevator.
An elevator in which an upper frame supported by upright columns and a ceiling plate supported by side walls of a cab are arranged on an identical plane has been proposed in response to this problem (see PTL 1, for example). In PTL 1, the number of components and the mass are reduced by employing the upper frame as a part of the ceiling.